ETH2CardanoSwap

To enable cross-chain swaps between Ethereum and Cardano on 1inch Fusion+, we implement a Hash Time-Locked Contract (HTLC)-based protocol that ensures trustless, atomic asset exchange. On Ethereum, we deploy a Solidity smart contract that locks ETH under a hashlock (secret hash) and a timelock, allowing the recipient to claim funds only by revealing the correct secret within the deadline. On Cardano, a Plutus smart contract mirrors this logic by accepting ADA under the same hashlock and timelock conditions. The swap flow begins when the ADA holder (Bob) creates a Cardano HTLC with hash H. The ETH holder (Alice) observes this and initiates the Ethereum HTLC using the same H. Bob then claims the ETH on Ethereum by revealing the secret, which Alice retrieves to unlock ADA on Cardano. An off-chain relayer or watcher monitors both chains, ensuring that secrets are propagated and refunds triggered on timeout. This system integrates with 1inch Fusion+ by acting as a resolver that facilitates cross-chain execution. Optional enhancements include partial fill support, wrapped tokens (wETH/wADA), UI integration, and relayer markets. This architecture preserves atomicity, supports on-chain enforcement, and leverages both EVM and non-EVM chains securely, extending Fusion+ beyond its native boundaries.

To enable cross-chain swaps between Ethereum and Cardano on 1inch Fusion+, we implement a Hash Time-Locked Contract (HTLC)-based protocol that ensures trustless, atomic asset exchange. On Ethereum, we deploy a Solidity smart contract that locks ETH under a hashlock (secret hash) and a timelock, allowing the recipient to claim funds only by revealing the correct secret within the deadline. On Cardano, a Plutus smart contract mirrors this logic by accepting ADA under the same hashlock and timelock conditions. The swap flow begins when the ADA holder (Bob) creates a Cardano HTLC with hash H. The ETH holder (Alice) observes this and initiates the Ethereum HTLC using the same H. Bob then claims the ETH on Ethereum by revealing the secret, which Alice retrieves to unlock ADA on Cardano. An off-chain relayer or watcher monitors both chains, ensuring that secrets are propagated and refunds triggered on timeout. This system integrates with 1inch Fusion+ by acting as a resolver that facilitates cross-chain execution. Optional enhancements include partial fill support, wrapped tokens (wETH/wADA), UI integration, and relayer markets. This architecture preserves atomicity, supports on-chain enforcement, and leverages both EVM and non-EVM chains securely, extending Fusion+ beyond its native boundaries.